#include "aftypes.h" /* this table was generated for AF_ANGLE_PI = 256 */ #define AF_ANGLE_MAX_ITERS 8 #define AF_TRIG_MAX_ITERS 9 static const FT_Fixed af_angle_arctan_table[9] = { 90, 64, 38, 20, 10, 5, 3, 1, 1 }; static FT_Int af_angle_prenorm( FT_Vector* vec ) { FT_Fixed x, y, z; FT_Int shift; x = vec->x; y = vec->y; z = ( ( x >= 0 ) ? x : - x ) | ( (y >= 0) ? y : -y ); shift = 0; if ( z < ( 1L << 27 ) ) { do { shift++; z <<= 1; } while ( z < ( 1L << 27 ) ); vec->x = x << shift; vec->y = y << shift; } else if ( z > ( 1L << 28 ) ) { do { shift++; z >>= 1; } while ( z > ( 1L << 28 ) ); vec->x = x >> shift; vec->y = y >> shift; shift = -shift; } return shift; } static void af_angle_pseudo_polarize( FT_Vector* vec ) { FT_Fixed theta; FT_Fixed yi, i; FT_Fixed x, y; const FT_Fixed *arctanptr; x = vec->x; y = vec->y; /* Get the vector into the right half plane */ theta = 0; if ( x < 0 ) { x = -x; y = -y; theta = 2 * AF_ANGLE_PI2; } if ( y > 0 ) theta = - theta; arctanptr = af_angle_arctan_table; if ( y < 0 ) { /* Rotate positive */ yi = y + ( x << 1 ); x = x - ( y << 1 ); y = yi; theta -= *arctanptr++; /* Subtract angle */ } else { /* Rotate negative */ yi = y - ( x << 1 ); x = x + ( y << 1 ); y = yi; theta += *arctanptr++; /* Add angle */ } i = 0; do { if ( y < 0 ) { /* Rotate positive */ yi = y + ( x >> i ); x = x - ( y >> i ); y = yi; theta -= *arctanptr++; } else { /* Rotate negative */ yi = y - ( x >> i ); x = x + ( y >> i ); y = yi; theta += *arctanptr++; } } while ( ++i < AF_TRIG_MAX_ITERS ); /* round theta */ if ( theta >= 0 ) theta = FT_PAD_ROUND( theta, 4 ); else theta = - FT_PAD_ROUND( theta, 4 ); vec->x = x; vec->y = theta; } /* documentation is in fttrigon.h */ FT_LOCAL_DEF( AF_Angle ) af_angle_atan( FT_Fixed dx, FT_Fixed dy ) { FT_Vector v; if ( dx == 0 && dy == 0 ) return 0; v.x = dx; v.y = dy; af_angle_prenorm( &v ); af_angle_pseudo_polarize( &v ); return v.y; } FT_LOCAL_DEF( AF_Angle ) af_angle_diff( AF_Angle angle1, AF_Angle angle2 ) { AF_Angle delta = angle2 - angle1; delta %= AF_ANGLE_2PI; if ( delta < 0 ) delta += AF_ANGLE_2PI; if ( delta > AF_ANGLE_PI ) delta -= AF_ANGLE_2PI; return delta; } /* well, this needs to be somewhere, right :-) */ FT_LOCAL_DEF( void ) af_sort_pos( FT_UInt count, FT_Pos* table ) { FT_UInt i, j; FT_Pos swap; for ( i = 1; i < count; i++ ) { for ( j = i; j > 0; j-- ) { if ( table[j] > table[j - 1] ) break; swap = table[j]; table[j] = table[j - 1]; table[j - 1] = swap; } } } FT_LOCAL_DEF( void ) af_sort_widths( FT_UInt count, AF_Width table ) { FT_UInt i, j; AF_WidthRec swap; for ( i = 1; i < count; i++ ) { for ( j = i; j > 0; j-- ) { if ( table[j].org > table[j - 1].org ) break; swap = table[j]; table[j] = table[j - 1]; table[j - 1] = swap; } } }